/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.ant;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.types.DataType;
import proguard.MemberSpecification;
import proguard.classfile.*;
import proguard.classfile.util.ClassUtil;
import proguard.util.ListUtil;

import java.util.*;

/**
 * This DataType represents a class member specification in Ant.
 *
 * @author Eric Lafortune
 */
public class MemberSpecificationElement extends DataType {
    private String access;
    private String annotation;
    private String type;
    private String name;
    private String parameters;

    /**
     * Adds the contents of this class member specification element to the given list.
     * 
     * @param memberSpecifications the class member specifications to be extended.
     * @param isMethod specifies whether this specification refers to a method.
     * @param isConstructor specifies whether this specification refers to a constructor.
     */
    public void appendTo(List memberSpecifications, boolean isMethod, boolean isConstructor) {
        // Get the referenced file set, or else this one.
        MemberSpecificationElement memberSpecificationElement = isReference()
            ? (MemberSpecificationElement)getCheckedRef(this.getClass(), this.getClass().getName()) : this;

        // Create a new class member specification.
        String access = memberSpecificationElement.access;
        String type = memberSpecificationElement.type;
        String annotation = memberSpecificationElement.annotation;
        String name = memberSpecificationElement.name;
        String parameters = memberSpecificationElement.parameters;

        // Perform some basic conversions and checks on the attributes.
        if (annotation != null) {
            annotation = ClassUtil.internalType(annotation);
        }

        if (isMethod) {
            if (isConstructor) {
                if (type != null) {
                    throw new BuildException("Type attribute not allowed in constructor specification [" + type + "]");
                }

                if (parameters != null) {
                    type = JavaConstants.TYPE_VOID;
                }

                name = ClassConstants.METHOD_NAME_INIT;
            } else if ((type != null) ^ (parameters != null)) {
                throw new BuildException(
                    "Type and parameters attributes must always be present in combination in method specification");
            }
        } else {
            if (parameters != null) {
                throw new BuildException(
                    "Parameters attribute not allowed in field specification [" + parameters + "]");
            }
        }

        List parameterList = ListUtil.commaSeparatedList(parameters);

        String descriptor = parameters != null ? ClassUtil.internalMethodDescriptor(type, parameterList)
            : type != null ? ClassUtil.internalType(type) : null;

        MemberSpecification memberSpecification = new MemberSpecification(requiredAccessFlags(true, access),
            requiredAccessFlags(false, access), annotation, name, descriptor);

        // Add it to the list.
        memberSpecifications.add(memberSpecification);
    }

    // Ant task attributes.

    public void setAccess(String access) {
        this.access = access;
    }

    public void setAnnotation(String annotation) {
        this.annotation = annotation;
    }

    public void setType(String type) {
        this.type = type;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setParameters(String parameters) {
        this.parameters = parameters;
    }

    /**
     * @deprecated Use {@link #setParameters(String)} instead.
     */
    public void setParam(String parameters) {
        this.parameters = parameters;
    }

    // Small utility methods.

    private int requiredAccessFlags(boolean set, String access) throws BuildException {
        int accessFlags = 0;

        if (access != null) {
            StringTokenizer tokenizer = new StringTokenizer(access, " ,");
            while (tokenizer.hasMoreTokens()) {
                String token = tokenizer.nextToken();

                if (token.startsWith("!") ^ set) {
                    String strippedToken = token.startsWith("!") ? token.substring(1) : token;

                    int accessFlag = strippedToken.equals(JavaConstants.ACC_PUBLIC) ? ClassConstants.ACC_PUBLIC
                        : strippedToken.equals(JavaConstants.ACC_PRIVATE) ? ClassConstants.ACC_PRIVATE
                            : strippedToken.equals(JavaConstants.ACC_PROTECTED) ? ClassConstants.ACC_PROTECTED
                                : strippedToken.equals(JavaConstants.ACC_STATIC) ? ClassConstants.ACC_STATIC
                                    : strippedToken.equals(JavaConstants.ACC_FINAL) ? ClassConstants.ACC_FINAL
                                        : strippedToken.equals(JavaConstants.ACC_SYNCHRONIZED)
                                            ? ClassConstants.ACC_SYNCHRONIZED
                                            : strippedToken.equals(JavaConstants.ACC_VOLATILE)
                                                ? ClassConstants.ACC_VOLATILE
                                                : strippedToken.equals(JavaConstants.ACC_TRANSIENT)
                                                    ? ClassConstants.ACC_TRANSIENT
                                                    : strippedToken.equals(JavaConstants.ACC_BRIDGE)
                                                        ? ClassConstants.ACC_BRIDGE
                                                        : strippedToken.equals(JavaConstants.ACC_VARARGS)
                                                            ? ClassConstants.ACC_VARARGS
                                                            : strippedToken.equals(JavaConstants.ACC_NATIVE)
                                                                ? ClassConstants.ACC_NATIVE
                                                                : strippedToken.equals(JavaConstants.ACC_ABSTRACT)
                                                                    ? ClassConstants.ACC_ABSTRACT
                                                                    : strippedToken.equals(JavaConstants.ACC_STRICT)
                                                                        ? ClassConstants.ACC_STRICT
                                                                        : strippedToken
                                                                            .equals(JavaConstants.ACC_SYNTHETIC)
                                                                                ? ClassConstants.ACC_SYNTHETIC : 0;

                    if (accessFlag == 0) {
                        throw new BuildException("Incorrect class member access modifier [" + strippedToken + "]");
                    }

                    accessFlags |= accessFlag;
                }
            }
        }

        return accessFlags;
    }
}
